The long range goal of this project is to use freeze fracture techniques and electron microscopy to study the structure of myelin and cell membranes in CNS tissue and in subcellular fractions. Current experiments include the examination of myelin related fractions (R. McIntyre, R. Quarles), and axolemma enriched fraction (J.M. Matthieu) and hexachlorophene intoxication in freeze-fracture replicas (P. Reier). BIBLIOGRAPHIC REFERENCES: McIntyre, R.J., Quarles, R.H., Webster, H. deF. and Brady, R.O.: Isolation and characterization of myelin-related membranes. J. Neurochem. 1977 (in press). Matthieu, J.-M., Webster, H. deF., Beny, J. and Dolivo, M.: Characterization of myelin and axolemma-enriched fractions from rabbit brain. Brain Res. Bull. 1977 (in press).